The present invention relates to a refrigerating device, in which an internal refrigerating compartment is cooled by a tubular evaporator through which coolant circulated by a compressor flows and which features a carrier plate and a tubular pipe arranged in contact with it so as to conduct heat. The tubular evaporator which is in close thermal contact with the internal refrigerating compartment is thermally screened from the environment by an insulation layer. The compressor is arranged outside the insulating layer and feeds compressed coolant to the evaporator at ambient temperature. As it passes a choke point of the evaporator the coolant is relaxed to a low pressure, which reduces the boiling temperature of the coolant to a value well below that of the ambient temperature. The vaporization of the coolant resulting from this causes the inner compartment to cool down. Gaseous coolant is sucked out of the compressor via a suction line.
With Rollbond evaporators which in general are constructed from two metal plates bonded together, of which in one there is embodied a serpentine coolant line, in general a collector is formed in the evaporator adjacent to the downstream end of the coolant line, which during an idle phase of the compressor traps unvaporized coolant and in this way prevents it being pushed out of the evaporator and into the suction line by coolant evaporating further upstream in the line. To also provide such a collector for a tubular evaporator is complex and expensive, since to do this it is necessary to tightly join together a number of tube sections with different internal widths. Instead of this, with conventional tubular evaporators an ascending outlet tube is frequently arranged directly upstream from the suction tube. While this outlet tube is not completely filled with liquid coolant, so that gaseous coolant can enter at the upstream, lower end of the outlet pipe, bubbles of the gaseous coolant can rise up through any liquid coolant which may possibly be present in the tube. If however the amount of coolant collected at the downstream end of the evaporator is greater than the ability of the outlet tube to accommodate it, liquid coolant gets into the suction line and cools this outside the insulation layer. On the one hand this results in a low thermal efficiency of the refrigerating device, on the other condensation water which precipitates on the outside of the suction line can result in damage to the appliance or can penetrate into the insulation layer and thereby adversely affect its insulation capabilities. To counter this danger, the amount of coolant in the refrigerating circuit of a refrigerating device is currently restricted in order to prevent sufficient liquid coolant from collecting so as to cause the outlet pipe to overflow. Such a restriction can however also adversely affect the efficiency of the refrigerating device.